Study of tablet-coating parameters for a pan coater through video imaging and Monte Carlo simulation

The movement of tablets in a pan coater and the exposure of different surfaces of tablets for deposition of coatings by spray-coating have been studied by video imaging and Monte Carlo simulation techniques. A representative variety of tablets of different shapes and sizes were used at different pan loads and at various pan speeds. A single “tracer” tablet was used to track the motion of tablets and coating variables such as circulation time, surface time, projected surface area and surface velocity of a tablet were determined from the video imaging experiments. The coating uniformity is described in terms of the coating variation from tablet to tablet CV(tt) and a new parameter CV(st) the coating variation on a single tablet. The effect of shape of tablets on coating uniformity was analyzed by introducing a “sphericity” of tablet (φ_s) into the CV models. The methodology, new models and the analysis developed here incorporating the additional parameters will help users to optimize the coating process in pan-coating operations.     

复方胆通片质量标准的研究

目的建立复方胆通片的质量标准。方法采用薄层色谱法鉴别方中的大黄、溪黄草与胆通;用高效液相色谱法测定羟甲香豆素和齐墩果酸的含量。结果薄层色谱法能明显检测出大黄、溪黄草、胆通,薄层图谱斑点清晰,阴性对照无干扰;羟甲香豆素进样量在4.92～49.2μg范围内呈良好线性关系(r=0.999 7),平均加样回收率为98.79%;齐墩果酸进样量在0.3～3.0μg范围内呈良好线性关系(r=0.999 3),平均加样回收率为99.90%。结论所建标准可用于复方胆通片的质量控制。     

In vitro and in vivo release of naltrexone from biodegradable depot systems

The aim of this study was to prepare poly(d, l-lactide) (PLA) microspheres containing naltrexone (NTX) by a solvent evaporation method, and to evaluate both in vitro and in vivo release characteristics and histopathological findings of tissue surrounding an implant formulation in rats.

This method enabled the preparation of microspheres of regular shape and relatively narrow particle size distribution. The in vitro release profiles of NTX from PLA microspheres showed the release of NTX did not follow zero-order kinetics. An initial burst release was observed, subsequently followed by a nearly constant rate of 0.4% per day after ten days. The cumulative amount of NTX released at the end of 60 days was 80%. Compressed microspheres showed near zero-order sustained release of NTX for 360 days. The plasma NTX levels in rats showed that for compressed microspheres NTX concentrations were constant and exceeded 2 ng/mL for 28 days. Throughout the 28 days of study, the implantations cause a minor inflammatory response, which can be regarded as a normal defence mechanism. The sustained release performance of NTX from the biodegradable depot systems may provide a reliable, convenient, and safe mechanism for the administration of NTX for the long-term treatment of opioid dependence.     

Tabletted soy protein cold-set hydrogels as carriers of nutraceutical substances

The swelling of soy protein filamentous hydrogels and tablets thereof and the release of riboflavin from these drug delivery devices were investigated under simulated gastrointestinal conditions in the presence or absence of digestive proteases. Microscopic examination showed riboflavin arranged into crystals dispersed randomly throughout the hydrogel and the tablet powder. Swelling experiments showed a comparable behavior of water uptake for hydrogel and tablet at pH 1.2 as well as tablet at pH 7.5, featuring a low swelling rate. Hydrogel at intestinal pH began to shrink after 1 h, which coincided with a loss its structure. Riboflavin release was faster at pH 7.5 than at pH 1.2 for both devices. Swelling was the principal mechanism of riboflavin release from tablets at pH 7.5, while drug-polymer interactions slowed this release at pH 1.2. In the presence of pepsin at pH 1.2, both devices showed slow zero-order release of riboflavin for 6 h, while both were digested completely in the presence of pancreatin at pH 7.5. These results suggest that these tabletted hydrogels and the hydrogels themselves might both be useful for transporting bioactive molecules through the gastrointestinal tract and delivering them in the small intestine. Considering their non-synthetic nature, they should be of great interest for the development of innovative functional foods.     

保健食品健脑益智片的试制

由石杉碱甲和卵磷脂制成保健食品健脑益智片 .在该产品的试制过程中 ,在压片工序出现了颗粒流动性差、吸潮粘冲、片子松散、撬盖、成型困难、基片崩解超限和微量功效成分—石杉碱甲含量不均匀等一系列难题 .通过采用新材料 ,改进制剂工艺 ,最终成功地解决了这些难题     

Young students using iPads: App design and content influences on their learning pathways

The past few years have seen an array of new technological gadgets arrive on the education scene, perhaps the best known of these being Apple's i-Device range, particularly the iPad. Such devices have been described by some as ‘game changers’, and promoted as a key component to stimulating much-needed educational reform. However, history suggests the hype and rhetoric surrounding these technological innovations has failed to match the reality of their performance, in action. Some have attributed this failure to a lack of alignment by teachers of pedagogical models with the potential of technologies, while others argue that claims made are simply unrealistic sales hype. Regardless, schools continue to be seduced by these new technologies, purchasing ever increasing amounts based on the alleged learning promises they offer their students.This study presents an innovative approach to exploring student interaction with iPad apps, and is an attempt to begin to unpack factors that affect their learning pathways, in an effort to improve the educational potential of these popular devices. It focuses specifically on design and content features of apps selected by an experienced teacher to enhance literacy, numeracy and problem-solving capabilities of her 5 year old students. Findings reveal a complex matrix of influencing factors. These include the effect of embedded pedagogical scaffolds (eg., modelling, reflection time), corrective and formative feedback, text-to-speech functionality, imposed interaction parameters, impediments (eg., web links, advertisements, buying content) and the entertainment/education balance. Arguments are made for researchers, teachers and developers to work together and adopt methodologies such as that introduced in this article, to gather data to radically improve the design of apps used by young students for learning.     

Bioequivalence evaluation of two formulations of doxazosin tablet in healthy thai male volunteers

The bioequivalence of two doxazosin 2 mg tablets was determined in 24 healthy Thai male volunteers after one single dose in a randomized cross-over study with a one week washout period. The study was conducted at Faculty of Pharmaceutical Sciences and Health Sciences Research Institute, Naresuan University, Phitsanulok, Thailand. Reference (Cardura®, Heinrich Mack Nachf. GmbH & Co. GK, Illertissen, Germany) and test (Dozozin-2®, Umeda Co., Ltd., Bangkok Thailand) were administered to volunteers after overnight fasting. Blood samples were collected at specified time intervals and plasma was separated. The validated HPLC method with fluorescence detection was used for quantification of doxazosin in plasma samples. The pharmacokinetic parameters, T_max, C_max, AUC_t, AUC_∞, T_1/2, λ_z, Cl and V_d, were determined from plasma concentration time profile of both formulations by using non-compartment analysis. The calculated pharmacokinetic parameters were compared statistically to evaluate bioequivalence between the two brands. The analysis of variance (ANOVA) using log-transformed C_max, AUC_t, and AUC_∞ did not show any significant difference between two formulations. The point estimates and 90% confidence intervals for C_max, AUC_t and AUC_∞ were within the acceptance range (0.80-1.25), satisfying the bioequivalence criteria of the Thailand Food and Drug Administration Guidelines. These results indicate that Dozozin-2® is bioequivalent to Cardura® and, thus, may be prescribed interchangeably.     

Fundamental and Derived Properties of Yam (Dioscorea Spp.) Starch Powders and Implications in Tablet and Capsule Formulation

A comparative investigation of the fundamental and derived properties of starches from some species of yam (Dioscorea spp.) was conducted with a view to establishing their suitability as excipients in tablet and capsule formulations. Variations were observed in the mean granular diameter of the starches obtained from the different Dioscorea species. Granular diameter ranged from 5.4 µm (Chinese yam) to 34.5 µm (Round leaf yellow yam). Chinese yam and Bitter yam had the highest specific surface area (625.91 m²/kg and 258.76 m²/kg, respectively) while Round leaf yellow yam and Negro yam had the lowest (117.4 m²/kg and 154.34 m²/kg, respectively). Chinese yam had the lowest granular volume (6.00 µm³), surface area (5.67 µm²) and granule surface‐mean diameter (6.74 µm), while Round leaf yellow yam had the largest mean granular diameter, highest granular volume (35.2 µm³), surface area (34.8 µm²) and granule surface mean diameter (35.88 µm). Particle size distribution plots of Chinese yam, Round leaf yellow yam and Negro yam displayed a Gaussian size distribution pattern while Bitter yam displayed a negatively skewed distribution. The variations observed in the granular size and shape may influence the observed derived properties of the starches.     

Using tablets in medical consultations: Single loop and double loop learning processes

ObjectiveThis paper investigates the influence of using tablet in waiting rooms and medical examinations on how physicians give information and how patients learn. It further assesses the factors that impact patient satisfaction.MethodsPatients and physicians in a primary care clinic were given a tablet device to search for health information in the waiting room, and when interacting with the physician, while physicians used the tablet device to share information with patients during the medical consultation. 82 patients completed a ‘pre’ survey on using tablets to search for health related information and a ‘post’ survey after their visit. Structural equation modeling was employed to analyze patient's perceptions.ResultsTablet use during consultation has a negative effect on patients' perceptions of physician information giving, but using the tablet in the waiting room has a positive impact on patient learning, perceptions of physicians' information giving and patient satisfaction.ConclusionsThis study indicates the importance of tablet use in ensuring information giving and patient learning. It further highlights the potential for tablets to promote single-loop learning in the medical encounter by better preparing patients for the physician's information giving. Tablets also enable double-loop learning, which leads to greater patient satisfaction.     

Acceptance‐Diffusion Strategies for Tablet‐PCs: Focused on Acceptance Factors of Non‐Users and Satisfaction Factors of Users

Among emerging devices propelling the growth of mobile devices, smartphones and tablet‐PCs are among the most recognizable. In this study, a research model is designed for exploring acceptance‐diffusion strategies for tablet‐PCs from the viewpoint of consumer perception, which is verified through a survey. The results of this study show that tablet‐PCs have great potential to be versatile, multifunctional devices, even though they are currently considered mostly as entertainment‐oriented rather than fulfilling the essential needs of everyday life. An analysis of the acceptance model for tablet‐PCs revealed that playability, cost level, functionality, and complexity significantly affect user acceptance. An analysis of the diffusion model, on the other hand, showed that playability and user interface have a significant influence on satisfaction, trust, and positive behavioral intention. We also found that cost level is not a major hindrance in the market diffusion of tablet‐PCs. The results of this study can be used to establish effective acceptance and diffusion strategies for tablet‐PCs and other emerging devices.